Many canine cardiac diseases are associated with left atrial (LA) remodeling and decreased function. For accurate assessment of LA indices, large-scale and prospectively determined reference intervals are necessary. To generate reference intervals of LA size and function using two-dimensional and three-dimensional echocardiography. Two hundred and one healthy adult dogs. Left atrial volume was assessed in right parasternal long-axis, left apical four-chamber and two-chamber views using monoplane Simpson’s method, two-dimensional and three-dimensional speckle tracking. Additionally, LA diameter was measured in right parasternal short-axis and long-axis views. Furthermore, LA function was determined by measuring strain and calculating LA fractional shortening and ejection fraction. All variables were tested for correlation to heart rate, age, and body weight. For LA diameter and volume, scaling exponents and prediction intervals were generated using allometric scaling. Reference intervals for LA function parameters were calculated using nonparametric methods. Left atrial diameter and volume showed a strong correlation with body weight. The scaling exponent for LA diameter was approximately 1/3 (0.34–0.40) and approximately one for volume measurements (0.97–1.26). Parameters of LA function showed no clinically relevant correlation with body weight, except for two variables, which showed a mild negative correlation. No clinically relevant correlations with age or heart rate were found. Reference intervals for linear, two-dimensional and three-dimensional measurements of LA size and function were established. The wide range of measurement methods offers the opportunity to select the appropriate reference values for LA evaluation depending on the available technical possibilities.

中文翻译：

---

使用二维和三维超声心动图获得的犬左心房大小和功能的各种测量的参考区间

许多犬类心脏病与左心房 (LA) 重塑和功能下降有关。为了准确评估 LA 指数，需要大规模且前瞻性地确定参考区间。使用二维和三维超声心动图生成 LA 大小和功能的参考区间。两百零一只健康的成年狗。使用单平面辛普森方法、二维和三维散斑跟踪在右侧胸骨旁长轴、左心尖四腔和两腔视图中评估左心房容积。此外，在右侧胸骨旁短轴和长轴视图中测量 LA 直径。此外，通过测量应变并计算 LA 缩短分数和射血分数来确定 LA 功能。所有变量都经过测试与心率、年龄和体重的相关性。对于 LA 直径和体积，使用异速生长缩放生成缩放指数和预测区间。 LA 函数参数的参考区间是使用非参数方法计算的。左心房直径和体积与体重有很强的相关性。 LA 直径的缩放指数约为 1/3 (0.34–0.40)，体积测量的缩放指数约为 1 (0.97–1.26)。 LA 功能参数与体重没有临床相关性，但两个变量显示出轻度负相关。没有发现与年龄或心率有临床相关性。建立了 LA 尺寸和功能的线性、二维和三维测量的参考区间。广泛的测量方法提供了根据可用的技术可能性选择适当的 LA 评估参考值的机会。